The rhino's horn consists of tightly compressed hair-like fibres and is attached to the skin, not the skull. Rhinos are fairly placid animals with poor sight but an acute sense of smell and hearing. They are fast-food grazers par excellence, capable of taking more than one mouthful per second when the grass is fresh and green. They tend to feed in the early morning and late afternoon and either rest in shade or wallow in shallow pools during the heat of the day. The mud wallows that they are known for is an effective tick-trapping technique - the parasites get caught in the mud, and when this dries and falls off the animals' skins, so do the insects.